Mysql Multiple Queries

When it comes to big data, it has to do with Alibaba. The world's leading E-commerce enterprise, the amount of data processed every day is unmatched by any other company, it is also transforming into a real data company--mysql is an important weapon in the transformation of Alibaba. 　　A database architect who interviewed Ali, who believes Ali has the best performance of open source MySQL, beyond any relational database and NoSQL. In the 2009, Oracle acquired the copyright of MySQL by acquiring Sun, and the industry began to question the use of Oracle ...

Intermediary transaction SEO diagnose Taobao guest Cloud host technology Lobby database optimization is a very complex task, because it ultimately requires a good understanding of system optimization. 　　Even though the system or application system does not know much about the optimization effect is good, but if you want to optimize the effect of better, then you need to know more about it. 1, the optimization of the system to run faster the most important factor is the basic design of the database. 　　And you have to be aware of what your system is going to do, and the bottlenecks that exist. The most common system bottlenecks are as follows: ...

MySQL optimization is very important. The most common and most needed optimization is limit. 　　The limit of MySQL brings great convenience to paging, but when the amount of data is large, the performance of limit is reduced dramatically. The same is 10 data select * FROM Yanxue8_visit limit 10000,10 and select * from Yanxue8_visit limit 0,10 is not a quantitative level ...

1, use the index to traverse the table faster. The index created by default is a non-clustered index, but sometimes it is not optimal. Under non-clustered indexes, the data is physically stored on the data page. Reasonable index design should be based on the analysis and prediction of various inquiries. In general: a. A large number of duplicate values, and often range query (>, <,> =, <=) and order by, group by occurred column, consider the establishment of cluster index; b. Column, ...

1, use the index to traverse the table faster. The index created by default is a non-clustered index, but sometimes it is not optimal. Under non-clustered indexes, the data is physically stored on the data page. Reasonable index design should be based on the analysis and prediction of various inquiries. In general: a. There are a large number of duplicate values, and often range query (>, <,> =, <=) and order by, group by occurred columns, consider the establishment of cluster index; Column, and each column contains duplicate values ​​can be ...

It is well known that the system reads data from memory hundreds of times times faster than it does from the hard disk. So now most of the application system, will maximize the use of caching (in memory, a storage area) to improve the system's operational efficiency. MySQL database is no exception. 　　Here, the author will combine their own work experience, with you to explore the MySQL database Cache management skills: How to properly configure the MySQL database cache, improve cache hit rate. 　　When will the application get the data from the cache? Database read from server ...

In this lesson, we want to learn how to increase the intelligent processing capacity of the Web page. Basic functions Welcome to the third and final lesson of this tutorial. If you've learned the first and second lessons, you've mastered the basics of installing and programming MySQL and PHP. Here are some of the other functions of PHP that might be useful to you and make your development process simpler. 　　First, let's look at the document. You should know some basic concepts of the header file, right? The header file is an external file whose contents are included in the main program. ...

PHP + MySQL combination is a common site to build, but how to use PHP to access the MySQL database through the Web? The following from the working principle of Web database architecture to talk about. Query the database from the Web: How the Web Database Schema Works 1. A user's browser makes an HTTP request that requests a specific Web page, where the Departing form is submitted to a php script file (eg, results.php) ; 2, Web server receives the results.php page please ...

In this lesson, we're going to do some more complicated work to show the data in multiple rows, the database exchanging data one, the while loop in this lesson, we will continue to drill down and use PHP and MySQL to write some simple and useful pages. 　　We start with the database we created yesterday and display the data in the library, but we'll touch it a little bit. First, we use the following code to query the contents of the database. <html> <body> <?php $db = Mys ...

NoSQL has been in vogue for a long time, so what exactly is the scene you need to use these "emerging things", such as http://www.aliyun.com/zixun/aggregation/13461.html ">mongodb?" Here are some summaries: you expect a higher write load by default, compare transaction security, MongoDB more attention to high insertion speed. If you need to load a lot of low-value business data, then MONGO ...